As Boeing decides where to locate production of its newest jet, the 777X, the Washington state senate voted over the weekend to extend $9 billion of tax breaks for the airplane manufacturer through 2040 and lock in Boeing’s current labor costs, trying to assuage concerns the company has about the state’s strong unions. Members of the International Association of Machinists and Aerospace Workers will vote on Wednesday on its proposed contract; if they don’t agree to it, the government’s offer is for naught.

Union president Tom Wroblewski tore up a copy of a proposed contract during negotiations on Thursday, calling it “a piece of crap.” Boeing promptly announced it would look to open the new operation elsewhere, but union leaders and the company then reached a tentative deal with a series of changes, such as signing bonuses and new retirement plan.

If the 31,000-member union votes down that proposal, a Boeing spokesperson said the company will “be left with no choice” but to look at other locations, such as South Carolina, Texas, and Utah, all three right-to-work states. Boeing already has operations in South Carolina: After a protracted fight with unions in Washington state and the federal National Labor Relations Board, production of another new Boeing jet, the 787 Dreamliner, began there in 2012. Japan is also seen as a possible manufacturing location.